This invention generally relates to methods for testing the strengths and endurance of particular muscles and muscle groups, and more specifically, to methods of this type where a subject is positioned and applies a force to a sensing means in such a way that this force is due solely, or substantially solely, to a selected muscle or muscle group.
An accurate and objective measurement of the strengths of individual muscles is very helpful for several reasons. For example, as a therapeutic aid, such a measurement helps a therapist identify specific muscles that need to be strengthened and to design a program that will help those particular muscles. Moreover, a quantitative measurement will tell not only which muscles are weak, but also how weak those muscles are. Also, as a person is undergoing treatment, an objective measure of the progress he or she is making, first, helps the therapist modify the treatment program, if necessary, and second, allows the patient to witness personally the fact that his or her muscles are getting stronger with therapy, which often encourages the patient to continue the treatment. In addition, often a patient may believe he or she is fully recovered and will discontinue treatment; however, an accurate, quantitative and objective measure of the strength of the muscles may show otherwise, and convince the patient to continue treatment.
As an exercise or athletic training aid, an objective and quantitative measurement of the strength of individual muscles will help a person or a trainer develop a highly personalized exercise program that concentrates on the muscles that need the most work. Occasional retesting will enable an individual, first, to observe personally the progress he or she is making, and second, will help show how effective a particular exercise program is and, if it becomes advisable to do so, how a program should be modified. An individual may test and record the strengths of his or her muscles while healthy to provide a personal standard; and if that person is later injured, he or she, while recovering, can compare his or her muscle strengths against that recorded standard to determine whether the muscles have adequately recovered before resuming a particular activity, thus lessening the risk of a re-injury or of a new injury.
Because the muscles of the human body are structurally and functionally so interrelated, it is difficult to measure accurately the strengths of many of the individual muscles and muscle groups. For example, to test the strength of a bicep muscle, a person may grip a sensing device and flex the bicep to apply an upward force on that sensing device. However, at the same time, the subject may, consiously or subconsiously bend his or her back or flex his or her legs to increase the force applied to the sensing device. If this happens, the total force sensed by the sensing device includes the forces developed by the back or leg muscles, and thus is not a precise indication of the force developed by the bicep. Similar difficulties are encountered when trying to measure the strengths of many of the other muscles and muscle groups; and because of these difficulties, prior to the present invention, there are no specific procedures to measure accurately and quantitatively the individual strengths of many of the muscles and muscle groups.